It is pretty obvious that regardless of further fiddling around with the inconsequential renegotiation, that David Cameron will advise us to vote to remain in the European Union. What is much less clear is the tone he will adopt in the referendum campaign. This will matter to his credibility in being able to continue as Prime Minister if we vote to leave. Negotiating the Brexit arrangements will be of genuine importance – in marked contrast to the tedious and semantic absurdities of the supposed renegotiation of our membership. Should we remain in the Single Market? What immigration rules should we set? What continued agreement (if any) should be sought on such matters as Overseas Aid, foreign policy and environmental protection?

There will be plenty of Eurosceptics who would demand Cameron’s resignation. But others who are not personally antagonistic towards him would doubtless urge him to stay in Downing Street according to the original timetable, so a matter a further three years or more.

If during the referendum campaign, Cameron bangs on about what a hopeless disaster Brexit would be, it would be hard for him to then present himself as the chap to make a success of it. However, if his message is more balanced then his survival would become much easier.

Of course, Cameron should and will stress during the campaign that the referendum means it is our decision and that our choice must be respected. He should also accept that the concessions he has achieved are modest – and more modest than he would have liked. He should concede that even with the concessions there will be remain serious burdens to our continued EU membership and that we could certainly prosper in the world with alternative arrangements.

Only after stressing all these points should he go on to say that “on balance” his own judgment is that remaining in the EU is the right decision. That would be a quite different tone from, for instance, warning against a Miliband Government or of Scottish independence.

In his Hamburg speech last night he said:

“When Britain says we need to have a Europe that respects nation states and that says we should be able to run our own welfare systems – those are calls that I believe resonate around Europe.

So if by working together we can achieve these changes, then I will unequivocally recommend that Britain stays in a reformed European Union on these new terms.

Of course, if we can’t then I rule nothing out.

But I believe we can – and if we do, I believe we can win that referendum and that will be good for Britain, good for Germany and good for the whole of Europe.

Because just as I believe that Britain will be safer and more prosperous in a reformed European Union, so too will Europe benefit from keeping its second largest economy, its largest defence power, a major diplomatic force in the world, and, of course, its second largest financial contributor.

And let me conclude by saying this.

Even if we secure the changes I am arguing for, the job will not be done.

There will be many things that would remain to be reformed and Britain would continue to stand alongside Germany in leading the way.”

The message: “Vote to remain and although the renegotiation isn’t enough we will try and secure more reform” is not convincing. On the contrary the more credible claim is that remaining members will not mean the status quo – but of ever more EU spending and interference. I suspect that most Conservative MPs, Party members and Conservative voters would both like the UK to leave the EU and for Cameron to continue as PM for the bulk of this Parliament. Those objectives are eminently reconcilable – but the more nuanced Cameron is during the EU referendum, the easier it will be to achieve.